Authors:M. Molnár, L. Hornyák, R. Nagy, E. Márki, and Gy. Vatai
Our experiments were based on a model solution containing five of the main pineapple aroma components. Both sweeping-gas pervaporation and vacuum-pervaporation methods were carried out. Measurements were performed at different temperatures and feed flow rates. The purposes of this study were to examine applicability of the two pervaporation methods in reference to the pineapple aroma recovery, the effects of the operating parameters on the process, and modelling the pervaporation process by resistance-in-series model. Higher enrichment could be reached with vacuum-pervaporation than the sweeping-gas method. The separation process is determined by the diffusion of compounds in the membrane, thus the resistance in the boundary layer at liquid side is negligible. Based on performed experiments, the pervaporation process can be applied in beverage industry for aroma recovery.
Authors:E. Márki, I. Vas-Vincze, L. Tóvári, and Gy. Vatai
One of the most important enriching materials at the processing of alimentary pastes is the egg, which usage is limited because of its water content. Removing water from liquid whole egg with membrane processes, such as ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) was applied for raising the solid content at a temperature of 25 °C at constant flow rate. The separation procedures were carried out on laboratory scale equipments. The initial solid content of the liquid whole egg was 24 refractive (Ref%). The effects of different recirculation flow rates and transmembrane pressure differences were investigated on the permeate flux of the liquid egg. The product had up to 30, 35.5 and 36 Ref% solids in case of UF, NF and RO, respectively. From the resistance data it is obvious, that the polarization layer resistances (RP) determine the values of the permeate flux. The total solid content of permeate was 0.3 and 0.1 Ref% in case of nanofiltration and reverse osmosis, respectively. On the basis of experiments main data of a continuous pilot scale system were calculated and simplified cost estimation was performed using recent economic data of year 2011.